It looks like you have already gotten some good advice. I am so sorry you are having problems, but please don't get discouraged like I did. I didn't think I would ever find the technique that worked best for me. While I messed around trying to find the right technicque, my quilts tops were multiplying. LOL I haven't read all of the replies, my suggestions below are probably in there somewhere becaue I think we all go through the same process. Don't give up.
1st - Just use a walking foot and do the stitch in the ditch. It's a charity quilt not a show at a quilt festival. The recipient is going to care about the colors and how it feels. I personally think that comfort quilts should have polyester batting in them with not much quilting because they are cosier to the feel.
2nd - cotton batting is the very best to start with. I tried FMQ with polyester batting and the only way that would work would be stretched on a long arm. It's probably one of my most favorite to cuddle under, but I am not very proud of the FMQ.
3rd - use machine quiltling thread
4th - make a bunch of table runners and use quilt patterns in them so you can "practice" how to use different designs and give them as gifts.
5th - It takes a few tries to learn how to handle all that fabric too. I saw someone on you-tube demonstrate her table area for FMQ on large quilts. She put a large table up against a corner and used a smaller table in an "L" shape to the left and put her machine table by it. This way the fabric doesn't fall on the floor. I have found that those gloves you can buy for machine quilting helps me a lot with moving the fabric where I want to.
6th - DON'T GIVE UP - you are on your way, you just don't know it.
7th - I have heard this advice from all the professionals that I know who do FMQ on their home sewing machines ..........PRACTICE, PRACTICE, PRACTICE, PRACTICE
good luck